Electrically driven clock



Jan. 9, 1934. H. KIENZLE 1,943,079

ELEC'I R IGALLY DRIVEN CLOCK Filed Jan. 8. 1930 Fig.1

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Patented Jan. 9, 1934 ELECTRIOALLY DRIVEN CLOCK Herbert Kienzle, Villingen, Germany Application January 8, 1930, Serial No. 419,346,

and in Germany January 12, 1929 13 Claims. (01. 58--26) My invention relates to improvements in electrically driven clocks having an auxiliary actuating-mechanism which under normal conditions, i. e.--while the current is on and the clock is worked by electricity--is locked, and which when the current fails is automatically unlocked and will instantly begin to drive the clock hands until the current is restored. Clocks of this type are known e. g. from U. S. Patent 1,283,434.

As a matter of fact, as is well known to those skilled in this field it occasionally happens that the auxiliary actuating mechanism of an electric clock and particularly its balance wheel fails to start working, after it has been atrest for a long period of time and during which period there was no failure in the current supply. Such failure may occur because the lubricating oil has become resinous and hardened, and through other causes.

The object of my invention is to overcome the said drawback and to provide an improved auxiliary actuating mechanism for electric clocks which practically ensures the retention of its selfstarting characteristic.

Another object of the invention involves the designing of the auxiliary clock actuating mechanism so that on being unlocked it will receive an additional positive operating impulse from its locking member.

Other objects aimed at by the invention and advantages obtained will be apparent hereinafter.

The nature and scope of the invention are briefly outlined in the appended claims and will be more fully understood by the following specification taken together with the accompanying drawing in which Fig. 1 is a front elevation diagrammatically showing by way of an example an electric clock having an auxiliary actuating mechanism and an automatic unlocking device of the improved type, the latter being in locked position,

Fig. 2 is a side elevation showing in a larger scale, the balance wheel of the auxiliary clock actuating mechanism and the principal members of its locking device,

Fig. 3 shows the improved auxiliary clock actuating mechanism unlocked, according to this invention, while the current is 9n,

Fig. 4 shows the auxiliary actuating mechanism electromagnetically unlocked by failure of current.

In all the figures of the drawing for convenience sake only the balance wheel 3 of the auxiliary clock actuating mechanism is shown, while the electric clock proper l is indicated by a rotary shaft 15, by which the hour hand may be driven, and by the electric motor 2 which may be of the so-called synchronous type running at uniform speed.

For the purposes of my invention, as indicated above, the auxiliary clock actuating mechanism is provided with a locking device adapted to be electromagnetically unlocked when the current fails and to be automatically unlocked at} regular intervals, independently of whether or not the current supply fails.

In the embodiment of the invention as shown by way of example the said locking device comprises a bell crank'lever 11 having a magnetizable member 16 attached which cooperates with the magnetic field of the motor 2.

A stud 19 or the like controls the outward movement of the flnger- 10 of lever 11 which is engaged by the lower end 8 of the locking lever 4, the latter being normally pulled toward the stud by a spring 9.

The upper end of the locking lever 4 is formed with a resilient arm bent to include three portions 17, 17' and 17", the portion 17" in its operative position engaging the balance wheel 3 as indicated in Fig. 2.

The locking lever 4 is pivotally attached at 7 to a double arm lever 6, l3, fulcrumed at 5 and being pulled toward the shaft 15 under the action of a spring 12. -The,,- latter thus maintains a contact member 13' on rm 13 in constant engagement with a cam,,0 disc 14, the latter being provided with a. recess 18.

The cam 14 is fixed to the rotary shaft 15,which is driven by the hour-hand movement of the clock, so as to revolve e. g. at the rate of one revolution within six hours. In this case the lever 6, 13 by virtue of the recess 18 having rounded edges, will have a reciprocating movement every six hours, and thus temporarily unlock the bal- 05- ance wheel 3 of the auxiliary clock actuating mechanism, as indicated in Fig. 3. When the member 13 rides into recess 18, the spring 12 pulls the lever 6, 13 upwards; however, since the lower portion 8 of the locking lever 4 is maintained against the finger 10, the entire locking lever 4 and bent arm 17 is pulled backward and away from the periphery of balance wheel 3, as denoted in Fig. 3.

As shown in Fig. 3' the laterally bent portion 17" of the resilient arm 17 of the locking lever by reason of its specific path of movement will give a positive impulse to the balance wheel 3 instantly and infallibly to operate provided that the actuating spring, or weight, of the auxiliary clock movement is wound up.

On sliding out of the recess 18 of cam 14 the double arm lever 6, 13 returns the locking lever 4 and its resilient arm 17 into its normally operative position and thus locks the balance wheel 3. That is to say, when the contact 13' rides out of the recess 18, the lever 6, 13 is pushed into the position shown in Fig. 1, with the result that the lateral portion 1'7" of the resilient member moves forward into locking engagement, as shown in Figs. 1 and 2, with the periphery of balance wheel 3.

In the event of the current supply failing and the magnetic field of the motor 2 disappearing the bell crank lever 11 will be swung by the action of spring 9 into the position shown in Fig. 4 so as to force the finger 10 against stud 19. In turn the locking lever 4 and its resilient arm 17 are thrown into their inoperative position i. e. unlocking the balance wheel 3 and giving the latter an additional mechanical impulse as referred to above.

It will be appreciated that when the current supply fails, the pressure of finger 10 on the lower portion 8 of lever 4 fails, with the result that the retractive force of spring 9 is unopposed. Naturally, the movement of the lever 4 takes place about fulcrum 7, with the result that the lateral portion 17" of the resilient member is moved out of engagement with the periphery of balance wheel 3; that is to say, in a direction opposite that in Fig. 3. Thus, in Fig. 4, the locking lever 4 is shown disposed in such a position that the lateral portion 1'1" would be out of engagement with the periphery of the balance wheel 3.

It will thusbe seen that there are two positions which permit the balance wheel to become operative. Should the contact 13' ride into recess 18 while the current is still off (that is, while the lever 16 is positioned as shown in Fig. 4) then the lever 4 will be pulled rearwardly to the position of Fig. 3, and the balance wheel will still be operative.

Various changes and modifications may be.

made in the design of electric clocks having an improved device as described ior periodically unlocking the auxiliary clock actuating mechanism without substantially departing from the spirit and the leading ideas of my invention, and I do not wish tolimit the invention to the particular construction shown.

' What I claim is:

1. The combination with a clock having an electric operating motor, which latter may cease operation, and auxiliary means for operating said clock when said motor ceases, of means for periodically releasing said first means for operation while said motor is operating.

2. In an electric clock, an electrical motor, a main movement element, an auxiliary movement device, means associated with the motor to render inoperative the auxiliary movement while the motor is operative, and additional means associated with the main movement element to periodically render the auxiliary movement operative while the motor is operative.

3. In combination, in an electric clock, a main movement, an auxiliary movement including a balance wheelfan electric motor for actuating said main movement, a locking means for said balance wheel, an electromagnetic means associated with said motor and adapted to render the locking means operative to the balancewheel when the current fails, and a device between the main movement and said locking means to periodically render the locking means operative to engage and disengage the balance wheel.

4. An electric clock including a rotatable shalt, an electric motor for driving said shaft, an auxiliary movement for said shaft including a balance wheel, a cam mounted on said shaft and provided with a recess, a pivoted locking lever including a resilient arm adapted to engage the periphery of said wheel, means for actuating said locking lever when the current fails thereby causing the arm operative to disengage the wheel, and a lever element, including means adapted to periodically ride into said cam recess, for periodically disengaging said resilientarm from said wheel while the current flows.

5. In a timing device comprising a rotatable element and an electric motor for driving the element, an auxiliary mechanism for continuing the motion of the element if current tails and the motor stops, and means for periodically rendering the mechanism inoperative while the motor is operative.

6. In a timing device, as defined in claim 5, means, associated with the rotatable element, for periodically actuating the last named means to render the mechanism operative.

7. In combination with a clock including a shaft and means for opereing said clock and revolving its shaft, said means including an electric motor, which latter may cease operation, auxiliary means including a normally restrained balance wheel for revolving said shaft to operate said clock when said motor ceases to operate, an arm for restraining said wheel, and means for periodically releasing said arm to exercise said wheel while said motor is operating, said latter means including a recessed disc carried by said shaft, a pivot pin carried by the clock, a lever pivoted on said pin and on which said arm is carried, and another pin carried by said lever for entering said recess during revolution of said shaft.

8. In an electric clock comprising an electromagnetic motor, time indicating mechanism driven by the motor, an auxiliary clock movement adapted to drive said time indicating mechanism, means including an electromagnet associated with said motor for maintaining said auxiliary movement inoperative while current fiows, and additional means connecting said first means and the time indicating mechanism and adapted to automatically and periodically render the auxiliary movement operative.

9. In a timing device comprising a main movement having a shaft and including an electric motor for actuating the shaft, a disk carried by said shaft and having therein a recess, a normally inoperative auxiliary movement, and means associated with said disk and including a pin periodically entering said recess for causing said means to render said auxiliary movement operative.

10.- In combination, translating means; a first and a second drive means therefor; means for rendering the second drive means inoperative while the first is operating and operative while the first is not operated; and means for at times automatically rendering the second means operative while the first means is operating.

11. In combination; indicating means; a first and a second drive means therefor; means automatically rendering the second drive means inoperative while the first is operating and operative while the first is not operating; and means 13. In combinationfindicating means; a first and a second drive means therefor; means automatically rendering the second-drive means inoperative while the first is operating and operative while the first is inoperative; means for automatically periodically rendering the second means operative while the first means is operative; and means automatically applying additional driving power to the second drive means when the latter is caused to become operative.

HERBERT KIENZLE. 

